1. Field of the Invention
The present invention relates to an image processing apparatus, an image processing method and a recording medium preferable for a game apparatus or the like usable in amusement centers and houses.
2. Description of the Related Art
With recent advancement of computer technology, video game apparatus using computer graphic technology has been widely used. This video game apparatus is widely accepted by users so that diversified kinds of the game apparatuses have been developed and diversified kinds of software have been supplied to the market.
The game apparatus having such an image processing function, generally, comprises a game control unit containing a control unit, an sound generating means such as a speaker and a display for supplying video images. In the game apparatus, a background scene displayed on a display is changed with a progress of a game and a character can be moved within that background scene in response to an instruction of a player. Seeing changes of the background scene displayed on the display with progress of the game, the player operates a control unit such as a joy pad to move the character within the background scene, enjoying that game.
There are various methods for creating the game screen for such a game apparatus. As one of the methods, if all the screen displayed on the display is created with polygon data, three-dimensional or perspective representation is enabled. Because image data of the game space is composed of three-dimensional data at this time, by changing an angle of a virtual camera (viewpoint of the camera) in the game space, images seen from all angles can be obtained, so that freedom of representation on the screen is increased tremendously.
Additionally, as a creation method for the game screen, a method using movie screen based on computer graphics has been well known. The movie screen based on the computer graphic mentioned here refers to a sequence of two-dimensional picture image data determined to move from some position to other position so that an angle for seeing the screen is determined. If this movie screen is used, a fine and beautiful screen can be ensured and further a load on the game apparatus for image processing is less than the other methods.
Under such an environment, a new game apparatus loaded with further another image processing function has appeared in actual entertainment business. This is a music game apparatus in which an object (character) displayed on the screen can be made to dance with a music. In the game apparatus, it is strongly desired that music tempo coincides with object motion. To move the character synchronously with music, a conventional computer system controls reproduction of music and an object motion on the basis of actual time.
In such a conventional game apparatus, in case where all images including the background and character are represented with polygon data, unless a large amount of polygon data are prepared, the screen is represented roughly and further, a joint portion between the polygon data and the other polygon data is represented, so that its entire representation becomes angular. If the background and character are composed of a large amount of polygon data, it takes a tremendous load on image processing although the screen is displayed finely, so that some extent of diversified representation can be achieved.
Further, in case of the movie screen creation method using the movie screen based on the computer graphics, because a displayed screen is two-dimensional data, its entire representation is flat, and therefore the three-dimensional representation is impossible. Further, because a camera angle is fixed in the aforementioned movie screen, the freedom of screen representation is very low.
On the other hand, in case of image processing for the aforementioned music game, a computation amount is large and control for the computation is complicated because reproduction of the music and motion of the object are controlled on the basis of the actual time.
Accordingly, an object invention is to solve the problems which the conventional game apparatuses have and then provide an image processing apparatus having such an image processing function, an image processing method thereby and a recording medium therefor.
More specifically, a first object of the present invention is to achieve an image processing capable of diversifying representation of a game screen, representing a motion of a display object moving on the game screen more smoothly, and reducing a drawing load remarkably.
Further, a second object of the present invention is to achieve an image processing capable of representing an image in which the motion of the object coincides (is linked) with reproduction of music easily and flexibly with less computation amount without depending on complicated control.
To achieve the above described first object, according to an aspect of the image processing apparatus of the present invention, there is provided an image processing apparatus wherein a first display object including a movie image and a second display object composed of solid image of polygon data are displayed on a display means, the image processing apparatus having an image processing means for carrying out image processing by setting up a simple model composed of three dimensional data for determining the precedence in erasing a negative face between the first display object and the second display object.
Preferably, the first display object composes a background of a game screen while the second display object composes a character displayed on the background. Further, of the first display object, only a portion in which the precedence of the polygon data needs to be determined is composed of the simple model.
For example, preferably, the simple model is three dimensional data composed of polygon data set up roughly.
According to another aspect of the image processing apparatus of the present invention, there is provided an image processing apparatus wherein a first display object including a movie image and a second display object composed of solid image of polygon data are displayed on a display means, the image processing apparatus having an image processing means in which a virtual camera for the second display object is set up and when the second display object moves over the first display object, motion of the virtual camera is controlled so that a position of the virtual camera substantially coincides with a camera angle with respect to the first display object and when the second display object moves over the first display object in an inverse direction, the first display object is reproduced with the inverse motion while the position of the virtual camera substantially coincides with the camera angle with respect to the first display object moving in the inverse motion.
Preferably, when the second display object moves from one section to other section of multiple sections produced by dividing a region in which the second display object should move of the first display object, a position of the virtual camera substantially coincides with a camera angle in each of the sections.
On the other hand, to achieve the first object, according to an aspect of the image processing method of the present invention, there is provided an image processing method for displaying a first display object composed of a movie image and a second display object composed of solid image of polygon data on a display means, the image processing method comprising setting up of a simple model composed of three dimensional data in part of the first display object while determining the precedence in erasing the negative face of the second display object using the simple model.
Further, according to another aspect of the image processing method of the present invention, there is provided an image processing method for displaying a first display object composed of a movie image and a second display object composed of solid image of polygon data on a display means, wherein a virtual camera for the second display object is set up and when the second display object moves over the first display object, motion of the virtual camera is controlled so that a position and angle of the virtual camera substantially coincide with a camera position and angle with respect to the first display object and when the second display object moves over the first display object in an inverse direction, said first display object is reproduced with the inverse motion while the position of the virtual camera substantially coincides with the camera angle with respect to the first display object moving in the inverse motion.
Further, there is provided a recording medium including a program for making a computer act as an image processing means or image processing method according to any one of the above described aspects.
By using the movie image in part of the background or the like to be displayed on a display means, as described above, screen representation can be diversified and the freedom of representation can be increased. At the same time, a drawing processing load is reduced remarkably and a moving state of a display object such as character on the movie screen can be represented smoothly.
Further, to achieve the second object of the present invention, there is provided an image processing apparatus wherein an image having a motion of an object existing in a virtual space is displayed on a screen of a display means in linkage with sound data. Preferably, a display control means for displaying a motion of the object in linkage with a beat of the sound data is further comprised.
Further, the image processing apparatus may further comprise a reproducing means for reproducing sound based on the sound data, wherein the display control means has: a first obtaining means for obtaining reproduction information of sound data by the reproducing means; a computing means for computing a reproduction position of a game with reference to the reproduction information of the sound data obtained by the obtaining means; a second obtaining means for obtaining data of the virtual camera and motion of the object based on a computation result of the computing means and motion progress data; and a generating means for generating image data for displaying motion of the object on a monitor screen.
Further, preferably, the first obtaining means is a means for obtaining reproduction sample number (ncount) and sampling frequency (freq) of sound data by the reproducing means and the computing means is a means for computing current frame number (frame) and beats with reference to the reproduction sample number (ncount) and sampling frequency (freq).
For example, the computing means is a means for computing current frame number (frame) and beats according to:
frame=ncount*FPS/freq
beat=frame/fpb
(where FPS is a frame number per second and fpb is a frame number per beat).
Further, the motion progress data may be data for allocating motions corresponding to beats of the sound data in time series.
Preferably, the virtual camera data is viewpoint information of the virtual camera in the virtual space and the generating means has a means for generating image data of the object with a movie image having viewpoint information coinciding with viewpoint information of the virtual camera as a background image.
Further, the generating means may be a means for generating the image data according to any one of the first generating mode for automatically setting motion of the object and the second generating mode for reflecting operation information from a player to motion of the object.
Further, the display control means comprises a means for forming a background image to be supplied to the object separately from the object image and a synthesizing means for synthesizing the object image with the background image in a state in which at least one of disposition conditions about the camera viewpoint and light source with respect to the object image and the background image is set substantially the same.
For example, the background image is a movie image.
Further, preferably, the sound data is supplied as ADX data which is ADX compressed.
Further, there is provided a recording medium for recording a program for making a computer carry out each of the respective means of the image processing apparatus which achieves the second object.
Consequently, it is possible to provide so-called music game in which the motion of an object on the screen dances with music. This game can be processed easily and flexibly with less computation amount without depending on any complicated control.
Meanwhile, the aforementioned recording medium includes, for example, floppy disc, hard disc, magnetic tape, CD-ROM, CD-R, DVD, ROM cartridge, battery back-up RAM memory cartridge, flash memory, involatile RAM card and the like. Further, the recording medium includes communication medium including wire communication medium such as telephone line and wireless communication medium such as micro wave. The Internet is also included in the communication medium mentioned here. In conclusion, any means having a predetermined function by down-loading a program on the computer is included in the recording medium of the present invention.